Electrical connector



March 29, 1966 W. D. JOHNSTON ELECTRICAL CONNECTOR Filed March 16, 1964 FIGURE 1 IN V EN TOR. WILLIAM D. JOHN S'I'ON United States Patent 3,243,755 ELECTRICAL CONNEC'I0R Wiiiiam D. Johnston, Ormond Beach, Fla, assrgnor to General Electric Company, a corporation of New York Filed Mar. 16, 1964, Ser. No. 352,224 Claims. (Cl. 33947) This invention relates to electrical connectors for detachably fastening two members together to provide a continuous electrical path. More particularly, the invention is concerned with an electrical connector having a locking feature provided by a straight line motion making use of the affinity of interlocking, conical springs.

Means for joining parts of an electrical circuit or for connecting electrical components together to provide circuit continuity are many and varied in the art. These devices may take many forms depending upon the nature of the connection to be made, the mechanical stresses that may become involved and the current carrying requirement. In some instances connections are actually welded together forming a semipermanent bonding where as in others it may be sufiicient to provide no more than a simple frictional contact between the connecting elements. Between'these' two extremes electrical connectors may take the forms of clamps, binding posts, clamping jaws screw and bayonet type connectors or spring-like insertable elements.

The present invention is directed to a simple construction utilizing a pair of conical springs of similar size and arrangement to provide an electrical connection whereby one of the springs acts as a male member and the other as a female member, the one being inserted into the other to provide a secure but detachable fastening.

A feature of the invention is the concept of a conical spring mating with a conical spring.

Conical springs of many sizes and configurations may be used varying from those having a major diameter of a fraction of an inch for use in so called electronic circuits to those having a major diameter of several inches for use in power circuits. These springs may be made from hard drawn copper, Phosphor bronze, beryllium, or alloys having good electrical conductivity, the male and female components of the connectors being identical except for the mode of connection to each by its circuit component. In other words, the resulting connectors following the teaching of this invention are of simple construction, have a minimum of parts, permit broad tolerances in manufacture. and automatically provide thermal compensation during actual use within a broad range of temperatures.

It is an object, therefore, to provide in this invention an electrical connector of simple construction and maximum operating reliability in the form of a conical spring.

It is another object of this invention to provide an electrical connector having identical male and female components, the one insertable into the other to eifect a detachably fixed electrical connection between electrical conductors to which the components are attached.

The principle of operation of the novel connector components in this invention is based upon the fact that with a pair of identical, conical springs, where one is inserted into the other, the inserted component will increase in rigity upon insertion into the other due to compression of its turns, the conical spring into which the insertion is made being free to float such as by being secured only at its major diameter. Upon withdrawal of the inserted component, which may be brought about by exerting force to separate the components, it becomes elongated thereby reducing its overall diameter within the other component so that the connection may be broken by a simple linear motion.

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Still another object of the invention is, therefore, to provide an electrical connector having detachalb'ly fixed components capable of being separated by the exertion of a simple linear force.

Another feature of the invention is the provision of an electrical connector by the use of a pair of mating, conical springs whereby connection therebetween is effected by mutual contact of a plurality of turns of the springs.

The invention is set forth with particularity in the appended claims. The principles and characteristics of the invention, as well as other objects and advantages are revealed and discussed through the medium of the illustrative embodiments appearing in the specification and drawings which follow.

In the drawings:

FIGURE 1 illustrates one form of conical spring from which identical connector components may be patterned.

FIGURE 2 illustrates the manner in which conical spring components may be joined by insertion of one into the other to form an electrical connection.

FIGURE 3 is a partial sectional view illustrating the actual physical connection between the connector components when the one is inserted into the other.

FIGURE 4 is an example of one form of the insertable component of the connector of the present invention.

FIGURE 5 is an example of one form of component into which the component of FIGURE 4 may be inserted.

FIGURE 6 is a partial sectional view of a pair of conical springs fully engaged according to .the invention.

Referring now to FIGURE 1 there is illustrated a conical spring 10 which may be made of hard drawn copper wire or tubing or of material having good electrical conductivity and mechanical resiliency. Two such springs are required for each electrical connector according to the present invention as indicated in FIGURE 2 wherein a conical spring 11, having turns 10a as illus trated in the process of being inserted into a similar conical spring 12 having turns 10b. Tabs 13 (attached to spring 11) and 14 (attached to spring 12) may be provided for attaching the connector components respec tively to the circuit devices desired to be connected together. Although in FIGURE 2 the spring 11 is shown being inserted into spring 12, the converse arrangement (insertion of spring 12 into spring 11) is also just as feasible since the springs 11 and 12 are substantially identical. In the later instance, after spring 12 is inserted into spring 11 the tab 14 would project through the apex of spring 1-1, this tab also being useful by way of being rotated to assist in forcing expansion and seating of the inserted spring 12 within spring 11. It is to be noted that when spring 12 is inserted fully in this manner the electrical connection to it would be similar to that of spring 11, i.e., by use of a tab 13 attached to the largest turn of the spring.

Referring to FIGURE 3 there is shown the engagement of the turns Ida of the inserted spring 11 as they engage with the turns 1% of spring 12 (as shown in FIGURES 2, 3 and 6). Normally each turn of the inserted spring will impinge upon and make contact with two turns of the spring into which insertion is made and vice versa (see FIGURES 3 and 6); however, in the event of distortion of a turn, as indicated by the center turn 10a in FIGURE 3, contact may be made only on a turn for turn basis between the two springs, this nevertheless providing reliable contact between the two components of the connector.

Connector components may be attached to cables and the like as shown in FIGURE 4 Where a conical spring 15 is attached at its major diameter 16 to a conductor 17 for insertion into a conical spring 18 carried in a cylindrical cup 19 attached to a conductor 20, the spring 18 being attached to the inside of cup 19 at its major diameter.

While the invention hast been explained and described with the aid of particular embodiments thereof, it will be understood that the invention is not limited thereby and that many modifications retaining and utilizing the spirit thereof Without departing essentially therefrom will occur to those skilled in the art in applying the invention to specific operating environments and conditions. It is therefore contemplated by the appended claims to cover all such modifications as fall within the scope and spirit of the invention.

What is clarned is:

1. An electrical connector for joining a pair of conductors consisting solely of a pair of substantially identical conical coil springs, one said spring being nested within the other to provide physical contact alOng adjacent coils thereof, said one spring being shaped to so nest upon linearly forcing same into said other spring, and means for attaching said conductors to said springs.

2. An electrical connector for joining a pair of conductors consisting solely of a pair of substantially identical symmetrical, conical coil springs, one of said springs being detachably nested Within the other to provide substantial physical contact along adjacent coils thereof, said one of said springs being shaped to so nest upon linearly forcing same into said other spring, and means for attaching said conductors to said springs.

3. An electrical connector for joining a pair of conductors consisting solely of a pair of substantially identical symmetrically, conical coil springs nested one within the other having the outside diameters of the turns of the inner spring impinging upon the inside diameters of the turns of the outer spring to provide physical contact, said springs being so shaped that they may be so nested by linearly forcing said springs together, and means for attaching said conductors to said springs.

4. An electrical connector for joining a pair of conductors consisting solely of a pair of substantially identical symmetrical, conical coil springs nested one Within the other having the outside diameters of the turns of the inner spring impinging substantially upon the inside diameters of corresponding turns of the outer spring to provide physical contact therebetween, said springs being so shaped that they may be so nested by linearly forcing said springs together, and means for attaching said conductors to said springs.

5. An electrical connector for joining a pair of conductors consisting solely of a pair of substantially identical symmetrical, conical coil springs nested one within the other for physical contact between the coils thereof and having the turns of the inner spring compressed and the turns of the outer spring expanded, said springs being so shaped that they may be so nested by linearly forcing said springs together, and means for attaching the said conductors to the said springs.

References Cited by the Examiner UNITED STATES PATENTS 881,181 3/1908 Egge.

1,421,017 6/1922 Lundberg 339 47 X 2,121,784 6/1938 Busby 8532 X 2,809,359 10/1957 Slick 339 252 X 2,972,125 2/1961 Temple 339-60 X 2,991,064 7/1961 D8 Jean 267-1 3,074,046 1/1963 Sullivan 339-256 3,165,576 1/1965 Lige 339-256 X PATRICK A. CLIFFORD, Primary Examiner.

JOSEPH D. SEERS, Examiner.

R. E. MOORE, Assistant Examiner. 

1. AN ELECTRICAL CONNECTOR FOR JOINING A PAIR OF CONDUCTORS CONSISTING SOLELY OF PAIR OF SUBSTANTIALLY IDENTICAL CONICAL SPRINGS, ONE SAID SPRING BEING NESTED WITHIN THE OTHER TO PROVIDE CONTACT ALONG ADJACENT COILS THEREOF, SAID ONE SPRING BEING SHAPED TO SO NEST UPON 